pgsql: Remove unneeded probes from configure and meson

Remove unneeded probes from configure and meson

7d854bdc5b72 has removed two symbols from pg_config.h.in. This file is
automatically generated. The correct cleanup needs to be done in the
build scripts, instead. autoheader produces now a consistent
pg_config.h.in, without the symbols that were removed in the previous
commit.

Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: /messages/by-id/1193764.1767573683@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8ab4b864c13f76512bd14591cc358df8c3d7c3a0

Modified Files
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configure | 2 +-
configure.ac | 2 --
meson.build | 2 --
3 files changed, 1 insertion(+), 5 deletions(-)